Songbirds truly worthy of the name are the members of the family Mimidae:
the mockingbirds, catbirds, and thrashers. Some of them, especially the
mockingbirds, borrow phrases from other birds—or from other sounds in
their surroundings—but they work them into improvisations that are rich
and musical, or at least interesting.

Bendire's Thrasher

Although a couple of species are common in eastern gardens, and various
types of mockingbirds occur throughout the Americas, the family reaches
its greatest development in the arid American Southwest. There are some
places where the Mockingbird and up to four species of thrashers may be
found nesting in the same patch of desert. Differences in the shapes of
their bills reflect differences in their feeding behavior, and probably
explain how all these related birds can coexist. For example, the Crissal
Thrasher, thrashing the soil with its big sickle-shaped bill, can probably
root out insects that are unavailable for the short-billed Bendire’s Thrasher.
There are also slight differences in habitat choice; Le Conte’s Thrashers,
for example, are found side by side with other thrashers in some places,
but their range also extends out onto barren saltbush flats where there
are few other birds.

Some thrashers are secretive birds, difficult to observe, but not the
Curve-billed Thrasher. Bold and inquisitive, it runs in the open and calls
“whit-wheet!” from prominent perches. In parts of the Southwest it has
adapted to advancing civilization almost as well as the mockingbird. Curve-billed
Thrashers may even thrive in the middle of cities, as long as they can
find a few cholla cacti in which to place their nests.

Distinguishing Features

Northern Mockingbird: Grayish-white plumage; flashes of white in the
wings and tail that show in flight. This bird is a remarkable mimic of
other birds in its area, a characteristic which gives it its genus and
species name; often heard singing on moonlit nights.

Curve-billed Thrasher: Well-curved bill; indistinct spots on breast;
gray-brown plumage; pale orange eyes; call is a sharp “whit-wheat”; song
is a musical series of notes and phrases with little repetition.

Habitat

Le Conte's Thrasher

The Northern Mockingbird frequents urban areas, ranches, densely wooded
washes, and shrub grasslands from the edge of the desert into the lower
elevations of mountains. Le Conte’s Thrasher prefers low, hot desert plains
with scant vegetation (such as creosote bush or saltbush flats). Bendire’s
Thrasher prefers the desert scrub of the Southwest. Curve-billed Thrasher
prefers the desert, arid brush, and shrubby woods; also found in southwestern
cities as long as cholla are available to provide nesting sites. Crissal
Thrasher frequents dense mesquite thickets along streams in the Sonoran
Desert; found in dense chaparral in southwestern mountains up to about
6000 feet. Gray Thrasher inhabits desert scrub and mesquite; found in
Baja California only.

• Behavior: The Northern Mockingbird forages by walking or running on
the ground or flying down to the ground from a perch; often opens and
closes wings, a behavior which causes insects to take flight. Perches
to eat berries.

Le Conte’s Thrasher foraging takes place on the ground where it uses
its bill to dig in the soil for food; feeding usually takes place early
morning or at dusk when insects are most active.

Bendire’s Thrasher forages mainly on the ground.

Curve-billed Thrasher forages almost entirely on the ground where it
uses its large bill to flick aside debris and dig in the soil in search
of food; berries are eaten while perched.

The Crissal Thrasher is seldom seen flying in the open, preferring to
keep within thick streamside vegetation; forages on the ground, usually
under thick brush; much of its food is found by digging in the soil or
hacking the ground with its heavy bill.

Gray Thrasher

The Gray Thrasher is often seen moving on the ground among the scrubby
vegetation in search of insects or perched atop a cactus or shrub.

Life History

The Northern Mockingbird builds a small stick nest lined with a few plant
fibers in large shrubs or small trees. Here it lays 3 to 4 bluish eggs
blotched with brown. These are incubated about 12 days by the female.
The young, which are fed by both parents, remain in the nest for 12 to
14 days. Mockingbirds can be quite aggressive towards dogs, cats, other
birds, and even humans who come within the vicinity of their nest.

Le Conte’s Thrasher mating pairs, which may mate for life, remain together
year-round. Cholla is a preferred nest site, although other low shrubs
may be used. The bulky twig nest, which is built by both sexes, is lined
with leaves, plant fibers, rootlets and sometimes with softer materials.
Pale blue-green eggs (2 to 4) are incubated by both parents and hatch
in about 15 days. The young leave the nest about 13 to 17 days after hatching.

The Bendire’s Thrasher nest, which is similar but smaller than other
thrasher nests, is built in cholla, yucca and various desert trees and
shrubs. The female lays 3 to 5 pale green eggs spotted with brown.The
young, which are fed by both parents, leave the nest about 2 weeks after
hatching.

Curve-billed Thrasher

Curve-billed Thrasher nesting begins in mid-March to early April. The
nest, a loose cup of thorny twigs, is built 3 to 5 feet above the ground
in cholla, yucca, or mesquite. It lays 2 to 4 turquoise-colored eggs that
are incubated for 12 to 15 days. The altricial young leave the nest at
14 to 18 days. Curve-billed Thrashers may tear apart Cactus Wren nests
when good nesting sites are at a premium.

Crissal Thrasher pairs may remain together year-round. The nest, which
is a bulky open cup constructed of twigs and lined with softer material,
is typically well concealed in mesquites, willows and other dense desert
vegetation. Should cowbirds lay eggs in the nest, the adults usually quickly
remove them. Pale blue-green eggs (2 to 4) are incubated by both parents.
They hatch in about 14 days. The young, which are fed by both parents,
leave the nest 11 to 13 days after hatching.